rsmith1jax,
Welcome, just sorry for why you are here. I have not had a cystectomy however, I have bookmarked a very good source on the 3 types of diversions. As it won't hyperlink go ahead and copy and paste it:
my.clevelandclinic.org/health/treatments/12546-urinary-reconstruction--diversion
Hopefully someone that frequents here can give you a better read on what the diaphramatic pressure issues might cause for an accomplished trumpet player. As I understand it there are different muscles used on some. I would certainly let your surgeon know about your concerns if you haven't already so they can be in the loop.
Keep asking away as you go. You will be helping someone else down the road!
